1. Field of the Invention
The present invention relates to an improved circuit construction techniques of a negative resistance circuit.
2. Description of the Related Art
Since a negative resistance circuit is utilized to improve Q of a tuning circuit, to compensate transmission loss of a transmission line and to constitute an oscillation circuit, it requires that design is easy, circuit construction is simple and it operates stably to high frequency.
A conventional negative resistance circuit employs various construction but each of them has the following defects.
Firstly, in a negative resistance circuit using a negative resistance element such as an ESAKI diode a desired resistance value can not be set.
Nextly, there is a negative resistance circuit using a multivibrator circuit wherein a loop gain is set not to oscillate the multivibrator circuit by inserting a resistor into an emitter circuit thereof but since gain of an internal amplifier therein can not be made large, a set negative resistance value thereof is easily influenced by means of change of temperature, source voltage, etc.